Electric plug



Patented Dec. 20, 1938 ELECTRIC PLUG Edwin William Bonson, London,England Application July 3, 1936, Serial No. 88,807 In Great BritainJuly 12, 1935 1 Claim.

In yconnecting plugs with insulating caps for wireless apparatus andother purposes, I use a metal part in any suitable conformation but formthe insulating body. cap or handle-part in two t 5 pieces, these beingprovided with male and female threads respectively so that when themetal part y with the usual connecting wire attached thereto is passedinto the one piece of the cap or body suit-v K ably formed with a slotor angular recess to retain l the metal part, the other piece of the capis screwed to it for purpose of binding the wire tightly to the metalplug and together provide the required insulating medium. 'I'heinvention is illustrated in the accompanyingdrawing in which:

Figure 1 is a side elevation of the male part of the device. Figure 2 isa similar viewv of the femalepart ofthe device, Figure 3 is a verticalsection taken on the line I--I of Figure 1, Figure 4 is a plan of Fig.1, Figure 5 is a similar view toFlgure 3 taken at right angles thereto,Figure 6 isr a vertical section of the female part of the device, Figure'7 is a form of metal plug suitable for use with the device, Figure 8 isa vertical ysection of the complete device assembled and 'showings theplug in position, the cable being omitted, Figure 9 is a similar view toFigure 1 f illustrating a modication in the construction of the deviceillustrated thereon, Figure 10 is a similar view to Figure 2 modified tocoact with 4the device shown in Fig. 9, Figure 11 is a plan 'of Fig. 10,Figure 12 is an elevation of a modified form of plug, Figure 13 is aplan thereof, and Figure 14 represents a sectional view of the modineddevice assembled, the plug being shown in f elevation. f

' Referring to the drawing, the insulating body, in accordance with theinvention, is constructed in two body parts, the one or top part aillusy trated in Fig. 1 having a male screw thread whilst Vtheother parte shown in Figure 2 is provided with a female screw thread that isinternally threaded, so as to interengage or co-act with said part a.The parts a and b of the insulating body are provided with a boretherethrough Whilst the rsection of the bore in the. part a is furnishedwith v rrecesses b bordering or on each side of said bore i v as shownin Figures 3 and 5.

It will be understoodl that the insulating plug made in two parts a, eare screw threaded to rinter-engage with each other and one or other ofthese parts may be externally milled for ease in dismantling or fittingtogether; the portion a or :i is centrally perforated with lateralrecesses b, the portion e being perforated in its shell and formed withan enlarged bore to accommodate the metal plug in such a manner that itis held immovably in position when the two parts a, e

are screwed together.

One part of the plug body the latter.

The metal plug may consist as in Fig.- 4 of a suitably shaped piece ofmetal as f perforated at its upper portion to receive the end of thewire or cable g which is twisted on itself and, when the two parts a, eor y', 1c are screwed home, will be forced tight on the widened upperpart of such plug, as shown in Fig. 8.

In Figs. 9 to 14 is illustrated a modification in which the body part :iis provided with an internal or female screw thread and the body part 7cis provided with an external or male screw thread and is adapted tointerengage or screw into the part Ic as will be readily understood.

In the construction shown in Figs. 12 and 13 the plug is formed with ahexagonal top m perforated to receive the Wire g which is flattenedthereon when the two parts y, lc are tightened together.

The hexagonal head may be slotted at p to receive the wire g and theperforation in part lc may be' hexagonal to receive the plug portion m.

I claim:-

An electric plug coupling comprising an insulated body consisting of amale and female interengaging screw threaded part, a vertical axialperforation in each of said parts, two oppositely disposed lateralrecesses adjacent one end of the axial perforation in the male part,said recesses being closed at their inner ends, an enlarged bore in thefemale part in axial alignment with the axial perforation thereof, ametal plug protruding through the latter perforation, said metal plughaving a widened centre part located in the enlarged bore aforesaid andterminating in a head held in the lateral recesses of the male part toprevent rotation thereof when the female part is screwed home.

EDWIN WILLIAM BONSON.

